LM25037EVAL: SS pin functionality

Anurag Singh

Intellectual 255 points

Part Number: LM25037EVAL
Other Parts Discussed in Thread: LM25037

Hi,

I am evaluating LM25037 design for a push pull transformer drive.

I have a question regarding using SS pin to disable the IC.

What i am observing is that with SS pin grounded , the output Out A and Out B turns on for a short time.

Please clarify if this is correct behaviour or output should be disable fully as SS pin is grounded.

8 months ago

0 Hong Huang 8 months ago

TI__Guru 60255 points

Hi,

Please provide the waveforms of SS, OUTA and OUTB, show after SS pull-down to ground, OUTA and OUTB still show waveforms for a short time.

Based on the datasheet Fig 13, pull-down SS will disable OUTA and OUTB right after pull-down to ground without continuing for a while.

0 Frank Rothoff 8 months ago

TI__Expert 6240 points

Hi Anurag,

Please also clarify if this a situation during power-up only?

0 Anurag Singh 8 months ago in reply to Frank Rothoff

Intellectual 255 points

Hi ,

Please find attached scope shots at power up and when ss pin is pulled to ground (during overload)

Power up

Overload

0 Hong Huang 8 months ago in reply to Anurag Singh

TI__Guru 60255 points

Hi,

The waveforms do not show your observation - OUTA and OUTB disabled right at SS pull down to ground. So your original observation is not supported by any evidence. I will close this thread as no issue is based on your waveform.

Power management

Power management forum

LM25037EVAL: SS pin functionality